Rep. Michelle Bachmann will formally begin her presidential campaign this morning in Waterloo, Iowa, riding a wave of positive news that has transformed her candidacy. Yesterday’s Des Moines Register Iowa Poll placed her in a statistical dead heat only a point behind frontrunner Mitt Romney at 22 percent. Coming less than two weeks after her smashing appearance at the New Hampshire Republican presidential debate, with Tim Pawlenty, her main competition in Iowa, faltering and with religious conservatives and Tea Party activists rallying to her side, it is clear in just a few weeks Bachmann has elevated herself from a second tier curiosity to a serious contender for the GOP nomination.

That’s an amazing accomplishment, but it does not get any easier for the congresswoman from Minnesota. With more than six months to go before the Iowa caucuses, Bachmann will be severely tested by increased and often hostile media scrutiny and the drudgery of retail campaigning in the early states as well as by the need to raise increasingly large amounts of money to fuel a national campaign. Yet while her opponents and media critics may think that gives Bachmann plenty of time to fail, they need to come to grips with the possibility a very different scenario may play out in the coming months.

It was a telling moment when Chris Wallace asked Bachmann yesterday if she was a “flake” during an interview on Fox News. Bachmann dismissed the charge with a dignity that showed she was anything but a “flake,” and Wallace has apologized. The interesting point about that exchange is it reflected exactly what many pundits and Republican power brokers have always thought about Bachmann. She was dismissed as a Sarah Palin knockoff, a Tea Party flamethrower or an evangelical extremist without the sense to know how to operate in Washington, let alone become a formidable presidential contender. Those who think the Republican Party is ready for a safe-sounding elite-pleasing “mainstream” candidate like Jon Huntsman believe Bachmann simply can’t win the nomination. They think the most she can hope for is a Mike Huckabee-style victory in Iowa that will be followed by defeat at the hands of a Republican who will supposedly have a better shot at winning in November.

The problem for Bachmann-bashers is she is not the political lightweight they take her for.

Bachmann has shown herself in recent weeks to be a polished and articulate candidate who has carefully modulated her statements and demonstrated she is ready for prime time. As analyst Nate Silver wrote in today’s New York Times, her polling numbers are simply terrific. She isn’t merely competing with the frontrunners who are supposed to be out of her class; she has the best favorability ratings of any candidate.

She starts out today with the enthusiasm and affection of large chunks of the most active elements of her party: religious conservatives and Tea Party activists. She must continue to excite them and get them to turn out to give her a victory in Iowa that looks to be more than possible. But the coming months will also give Bachmann the chance to become something more than just the standard bearer of the right wing of the GOP. In order to do that, she will have to stay on message, avoid foolish mistakes and also develop a coherent approach to foreign policy that will make her sound like someone who could actually be president. If she does all that (and that’s not a small “if”), anyone who thinks she can’t be the person accepting the Republican nomination in Tampa next August may be making a huge mistake.