There was no suspense attached to Jeb's decision about who to endorse. Bush the Elder had endorsed Romney months ago and it was believed that even if he felt otherwise, Jeb would not go against his father.

That said, in politics, timing is everything. And Jeb picked the perfect time to give Mitt his blessing.

The Hill:

Former Florida Gov. Jeb Bush endorsed Mitt Romney's presidential campaign on Wednesday and called for the Republican Party to unify around the former Massachusetts governor.

"Primary elections have been held in 34 states, and now is the time for Republicans to unite behind Gov. Romney and take our message of fiscal conservatism and job creation to all voters this fall," Bush said in a statement.

The Romney campaign responded with a statement that looked to build on that sentiment, calling the endorsement a "key moment in the presidential contest."

Bush, an influential figure in the party, made his announcement the day after Romney won a double-digit victory in Illinois' GOP primary.

His endorsement adds to Romney's momentum and serves as a sign that the Republican establishment is rallying around its frontrunner, who appears to have an insurmountable lead in the GOP delegate race.

President Obama's campaign team tried to down play the endorsement.

"It kind of felt like Jeb Bush was holding his nose in making that endorsement," campaign adviser Stephanie Cutter said on MSNBC.

Meanwhile Rick Santorum, Newt Gingrich and Rep. Ron Paul (R-Texas) have refused to exit the presidential race, with Santorum and Gingrich both signaling their intention to stay in the contest through the GOP's convention in August.

Gingrich won't listen to anyone, but Santorum wants a future in the party and a few more endorsements like Jeb Bush's -- as well as a loss in Louisiana this Saturday - just might convince him to pull out.

The latest poll, taken before the IL primary, shows Santorum with a 14 point lead in Louisiana. But Mitt is riding a wave and he will almost certainly narrow that gap. A surprise victory by Romney in LA would deal a mortal blow to Santorum and could send him to the exits.