With Rick Santorum's exit from the GOP presidential race this week, the general election contest between Republican Mitt Romney and President Obama quickly kicked into gear. Romney is starting the battle in a hole after a brutal primary season that cratered his favorability ratings and has him trailing the president in most national polls — as well as in key swing states and among crucial demographics. Luckily, pundits have no shortage of (often cynical) advice. Here, six things Romney must do to turn things around and triumph in November:

1. Motivate the GOP base
It's no secret that Romney has had trouble winning over conservatives and evangelical Christians. If even 5 or 10 percent of them stay home on election day, it could tilt the balance, says Affan Chowdhry in Canada's Globe and Mail. "Bottom line: The Romney campaign needs to fire up the conservative base." His "best bet is to emphasize the overwhelming urgency of defeating Obama," says Byron York in The Washington Examiner. Republicans may be divided on lots of issues, but they are "totally, completely, and unalterably united" on that goal.

2. Make peace with Santorum
"The most important endorsement Romney must secure" is that of erstwhile GOP rival Rick Santorum, say Jonathan Martin and Reid J. Epstein at Politico. The Pennsylvanian's imprimatur would help assuage doubts among reluctant social conservatives. Easier said than done, however: Santorum didn't even mention Romney by name when he dropped out, and he's likely nursing hurt feelings after some brutal attacks by Romney. "But [Santorum] has needs, too — namely a pile of campaign debt" — and generosity from Team Romney could help bring him into the fold.

3. Sprint toward the political center
Romney's in a pickle, says E.J. Dionne in The Washington Post. How does he rev up his conservative base while winning back crucial centrist voters who view his swing to the right, and today's GOP generally, with deep skepticism? "The conventional wisdom is that... Romney should shake the Etch A Sketch and begin to emphasize some of his moderate positions," says The Washington Examiner's York. He couldn't do that with the conservative Santorum nipping at this heels, but with the primary essentially over, "Romney should be free to shift" now.

4. Mend fences with women
Recent polls show Romney losing the female vote to Obama by huge margins, and he's responded by sending in his wife to vouch for him, says Ruth Marcus in The Washington Post. Sorry, but "outsourcing the job to his wife" isn't cutting it. Female voters may seem foreign, but "even if you're not fluent in their language, they might appreciate if you gave it a try." Why not talk up stories of "workplace Mitt promoting women or adopting family-friendly policies"?

5. Peel off Obama's Latino supporters
In the GOP primaries, "Romney positioned himself as the severe conservative on immigration," creating a massive "deficit with Latinos," say Benjy Sarlin and Evan McMorris-Santoro at Talking Points Memo. But he can still undo some of the damage, either by picking a Latino running mate, or "suppressing the Latino vote with negative attacks on Obama," spending heavily to "dissuade Latinos from supporting the president."

6. Attack, attack, attack
Romney needs to attack Obama at least twice as hard as he hit Newt Gingrich and Santorum, says Anton Wahlman at The Street. Unlike the affable loser John McCain in 2008, Romney must bury Obama in vicious attack ads. And I mean "unrestrained DEFCON-1 political warfare." Really, "if Romney's TV ads don't cause unprecedented controversy, dramatically dwarfing LBJ's 1964 'Daisy girl countdown' TV ad in the 'below the belt' department, Obama has a good chance of winning in November."

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