Campaign finance reports to provide window into health of Jeb Bush's campaign

Later today we'll get insight into the financial health of Jeb Bush's campaign, as FEC reports are due.

There's been speculation about Bush struggling to pull in hard dollars directly to his campaign and reports of belt tightening to mollify anxious donors.

Bush is expected to top the $6 million Marco Rubio has reported. But what's key is cash on hand. Rubio says he has about $11 million.

We're told Bush will make his number public by early afternoon; Rubio's report may come later in the day.

Bush also plans to release names of bundlers but as the Wall Street Journal reported, he's dropping the threshold to $17,600. That means a lot of people will be listed, obscuring the big whales. Rubio will not voluntarily release bundlers; only the names of lobbyist bundlers, as is required by law.

Bush and Rubio both benefit from super PACs (with Bush killing the field) but those reports are not due yet. Rubio has also greatly benefited from a "dark money" group that has already run four TV ads on his behalf.