Guns are rising to the forefront in what looks like the most competitive state Senate race on the 2018 Florida ballot, the battle for the District 18 seat held by 2nd Amendment rights advocate Sen. Dana Young, R-Tampa.

Over the weekend, Young's Democratic opponent, Bob Buesing, blasted her for missing votes on three key amendments during the Senate's unusual Saturday session to debate legislation responding to the Marjory Stoneman Douglas High School shooting.

Young responded that Buesing is "attempting to score political brownie points from a non-issue," and that she wasn't trying to dodge any votes.

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Instead, she said, she had to step off the Senate floor briefly during the eight-hour session, and recorded positions afterward on the votes she missed – all in the majority, so they wouldn't have affected the outcome.

Young voted in favor of the final bill as it passed the Senate Monday.

But the flap over her Saturday whereabouts is an early indication of the likely tone of the fight over the Senate seat.

It's considered one of the two best chances in the state for Democrats to flip a Republican-held seat, and it's likely to be the single closest Senate contest.

That means both parties will fight to the max over the seat with campaigns that will cost millions. Buesing, criticized by some Democrats who say he wasn't aggressive enough when he lost to Young in 2016, has vowed a tougher campaign this year.

"Dana walked right out of the chamber as the vote was called," he said in a news release. "Dana has made it clear: she will protect the NRA's priorities at all costs, including the safety of our school children."

"When she did show up she voted to arm teachers and refuse to ban assault weapons," he added in an interview.

He said Young's "refusal to vote is an indication of how nervous she is, and should be. The gun issue is the number one issue right now and will be in November."

Since the high school shootings, Buesing has stated his support for an assault weapons ban every time he's introduced in public.

He said he plans to make campaign use of a photo from a mailer Young used in her 2010 state House campaign, showing her aiming what appears to be an assault-style rifle, with a large American flag and a copy of the Constitution in the background, in which she advertised her NRA "A" rating.

During the Saturday Senate session, Young missed three amendment votes.

One would have banned assault rifles, the main focus of Democrats and student protests following the high school shooting. Another would require that law enforcement be notified of an attempt to buy a gun by a person prohibited from buying one, and the third would tighten requirements for storing firearms around minors.

Young opposed all three, and all were defeated by margins of three votes or more without her vote.

She recorded her positions against the assault weapons ban and law enforcement notification after the votes Saturday. She recorded her position against the storage amendment later when asked about it by a reporter, saying she was unaware she had missed that vote.

Young answered a quorum call immediately before the weapon ban vote, but said she then had to leave the floor briefly and didn't get back in time to vote on it and the notification amendment that followed.

Via email, she said the legislative process "often includes impromptu meetings with other senators off the Senate floor to ensure that bills and/or budget priorities of the Tampa Bay area are front and center, particularly on a day when we were on the floor for eight hours straight.

"The fact that Mr. Buesing is singularly focused on issuing press releases and attempting to score political brownie points from a non-issue shows that he puts his political ambitions ahead of our community."

The Tampa-centered district is one of two in the state held by Republicans but won by Democrat Hillary Clinton in 2016 – she led there by 5.5 percentage points.

In the same election, Young beat Buesing by 7 points, 48-41 percent, while no-party candidate Joe Redner got 9 points.

Young's campaign, her political committee and the Republican spent an amount estimated by Democrats as $5 million to $6 million on the race, figures Young doesn't dispute.

Redner has previously been a Libertarian, but is known for liberal views on the environment, education and other areas.

Political data analyst Matthew Isbell, a Democrat, said most of Redner's votes probably would have gone to Buesing, based on Redner's issues stances and on analysis of Redner's support.

Redner got the most support, Isbell said, from areas that went most heavily for Clinton.

But even with Buesing taking most Redner votes, the race would have been extremely close, he noted – Young was near a 50 percent vote total.

In an election year that could trend more Democratic, he said, that's likely to make the district the closest and hardest-fought state Senate race.

The vote on the assault weapons ban, which lost 20-17 and would have been 21-17 with Young's vote, shows the importance of one or two seats.

Democrats currently hold 15 of the 40 Senate seats and Republicans 23, with two open seats likely to split between the parties.

Two Republicans joined Democrats voting for the ban – Anitere Flores and Rene Garcia, who both hold Democratic-leaning districts in Miami-Dade County. With two more Democrats in the Senate, that would have been enough to pass the ban.