Here's Why Jeb Bush's Super PAC Is Spending $1.4 Million To Attack Marco Rubio

After months of speculation over what, precisely, it was doing with the tens of millions of dollars in its coffers, Jeb Bush’s super PAC, Right To Rise, announced Tuesday that it plans to run attack ads against Sen. Marco Rubio (R-Fla.) in Iowa. 

It was a somewhat confounding announcement, and not just because Rubio is Bush’s protégé and Iowa is a state that Bush, a former governor of Florida, has virtually no chance of winning. The subject of the ad -- Rubio’s poor attendance record at national security hearings -- is one that Bush already tried to capitalize on, only to swing and whiff during a now-infamous October debate performance.

Right To Rise says it is putting $1.4 million behind the spot over the next two weeks -- no small amount, even considering the elevated rates that super PACs must pay to reserve ad time. Which, in turn, raises the question of just what the honchos at that operation are thinking.

The answer is threefold.

First and foremost, the agreement in Bush world is that the Iowa contest has become a race for third place, behind Sen. Ted Cruz (R-Texas) and Donald Trump . The candidate who wins the bronze in Iowa will be able to claim to lead the “establishment lane” of the GOP field. Bush’s main competitors for this semi-dubious distinction are Rubio and New Jersey Gov. Chris Christie.

Still, Bush enjoys a luxury that Rubio and Christie don’t: He doesn’t hold any elected office at the moment, and therefore he can’t be accused of neglecting his job. Or, to put it another way, he won’t be dogged by infographics like the one C-SPAN tweeted on Monday, which listed Rubio as the senator with the worst attendance record this year, making just 64.6 percent of the chamber’s votes.

Which leads to the third reason that Bush’s super PAC is doing this ad: The "attendance record" line of attack is a nuisance for whomever it targets. And no one knows that better than Rubio’s own team.

In 2014, Conant and Todd Harris, a top Rubio strategist, were once again in Iowa, this time working for state Sen. Joni Ernst’s campaign for U.S. Senate . Ernst ended up winning, thanks in large part to a series of ads hammering the Democrat in that race -- U.S. Rep. Bruce Braley -- for, you guessed it, missing committee hearings to attend fundraisers.