I sat with an old friend recently, a politically interested but rather apolitical businessman, as he lamented the state of politics today and the state of the Republican Party."If this is the Republican Party, then I'm not a Republican," he said. "I don't know what I am now, but it's not Republican."Still other Republican friends lay out a passionate defense of the president and make the case that he is exactly the type of disruptive leader the party and the country need to break through the entrenched, intractable gridlock in Washington.It is clear that seven months into his presidency, Donald Trump — to be generous — has divided the nation and the Republican Party.Count me in the camp of those who believe the president is an ill-tempered, unqualified and at times dangerous leader of the free world. He is a very poor reflection of the Republican Party that I call my political home.In December 2015, I stood in the well of Congress and called on Trump to drop out of the presidential race following his Muslim ban pronouncement. I didn't support him in the 2016 primary, nor did I support him in the general election. Today I see a failed president, not a national leader. Though I once eschewed the "Never Trump" label, in practice it's a fair description.Without a dramatic change of course by the president, I plan on being very active in organizing a primary challenge to Trump in 2020 if he seeks re-election.Many may view a primary challenge as harmful to the Republican Party, but I anticipate a primary challenge to this president just might save the party from its demise. It's not because we could defeat an incumbent president through a primary challenge from within his own party. The lessons of history prove that is a highly unlikely endeavor.It's because a healthy, robust, competitive primary challenge to this president in 2020 might just prevent the Republican Party from splitting in two — prevent it from diluting constituencies into three main political parties as we saw most recently in 1992 with the emergence of Ross Perot and his Reform Party. That split allowed President Bill Clinton to emerge with only 43 percent of the national vote.I'm a modern-day Bull Moose Republican who along with millions of other center-right voters struggle to find a home in the small tent of today's Republican Party. I believe in conservative principles rationally applied to governing a relatively purple nation. And I believe the GOP should be a leader, not a laggard, on commonsense solutions to critical issues of the environment, equality, campaign finance reform, the Second Amendment and other issues that will define our era.But just I struggle at times to find a place in the GOP, it is equally clear there is no room in the Democratic Party for anyone with center-right solutions.An effort to mobilize a center-right voting bloc as an independent party would be herculean effort and history has proven it won't work, from the Progressive Party that splintered from Republicans in 1912 to the Perot movement of 1992. And most importantly for those of us loyal to the Republican Party, it would forever betray the Grand Old Party we still firmly believe in.But a credible, competitive and constructive primary challenge to Trump would give safe harbor to millions of GOPers who still believe in the party, just perhaps not this president. It would keep the feud within the family, and it would keep the family together.The worst thing Republicans can allow to happen as a party is to let the fractures this president has created lead to a legitimate breaking off of a center-right third party. Instead, by organizing a primary challenge to the president now, we can restore a place within the party for mainstream Republicans to call home and provide renewed leadership within the party for the Teddy Roosevelts, Dwight Eisenhowers and Abraham Lincolns among us who once made our party great.On Jan. 21, 2021, whether Donald Trump is a former president or reinaugurated, the GOP will begin anew the search for its next leader. If sensible, patriotic and, yes, loyal Republicans organize a challenge to the president now, the answer to the GOP's post-Trump dilemma will be just within reach.David Jolly is a former Republican member of Congress from Pinellas County, current instructor at the University of South Florida and frequent political commentator on MSNBC, CNN and other news outlets.