Sarah Palin’s presidential prospects continue to slip. But there are good reasons not to count her out quite yet.

Steve Kornacki has a nice post detailing how far Palin’s presidential stock has fallen, and Paul Waldman says she’s done. I have no reason to believe she’ll actually enter Republican presidential primaries and caucuses in 2012. But it’s too early to say that if she does enter she would be irrelevant. She wouldn’t.

The truth is that Palin remains the only real first-tier presidential candidate the Republicans have — the only candidate who has been on a national ticket. Should she decide to run an active campaign, she would likely recover a good bit of the ground she has lost, just by repositioning herself as a real politician and abandoning her current incarnation as a reality TV star. It’s still not too late for her to give a series of serious policy speeches; not too late for her to put together a real campaign staff; not too late for her to crisscross Iowa and New Hampshire; and not too late, certainly, for her to raise tons of money for a campaign.

To be sure, Palin retains the same drawbacks that she’s had all along, and so far she hasn’t done much to erase them. She’s a first-tier candidate, albeit one with very serious disadvantages, both for the general election and for nomination politics.

But as a first-tier candidate, a late start wouldn’t really be a major disadvantage. It’s not as if she would be Gary Hart in 1988, George McGovern in 1984, or Gene McCarthy in 1972 — a former heavyweight reduced to an object of curiosity. If Palin does wind up entering the race and running an active campaign, she’ll almost certainly be a major player.