Given a very realistic possible outcome of the Hayworth-McCain race in Arizona, this is an appropriate hypothetical for today:

What would have happened if McCain lost his Senate seat to a Democrat in 1998?

All other things remain equal.  We’ll say McCain still tried to get the Presidential nod in 2000 and lost.  We’ll also presume that the hypothetical Democrat who beat him retains that seat to this day.

First the down side:  no Sarah Palin.  He would not have been around to run in 2008, and thus would not have introduced us to someone who will hopefully be a far more serious Republican presidential nominee than he was come 2012.  Granted, he only recruited her to save his own posterior, but there’s no complaining about the outcome.

Up side?

1. No McCain-Feingold.  Feingold may well have introduced the bill without him, but there would be no militant RINO driving it hard from the other side of the aisle to make his media friends happy.  Bush wouldn’t have signed it before cowering under his desk, and that whole mess likely would never have happened.
2. Every McCain-Democrat bill ever introduced in the Bush terms would have lost its cover of bipartisanship.  McCain has been involved with some massively bad bills (amnesty, cap-and-trade, the aforementioned “campaign finance reform”) that would not have had the same drive without him.
3. Lindsey Graham might still be around as a RINO squish, but not a militant RINO pretending to leadership.  He certainly wouldn’t be telling his constituents that he’s voting for Kagan because Jesus said so.  That magnitude of pomposity, arrogance, and moral vanity in him might not have been but for his contact with McCain.
4. The Gangs of Fail would not have existed.  No Gang of 14, and no Gang of 10 in 2008 to help deflect Pence’s energy initiative.  No, McCain wasn’t involved in the Gang of 10, but a lot of Senators inspired by him were.  Some squishes would still have folded every now and again, but nothing so in your face as a Senate gang.
5. 2006 and 2008.  They probably would have occurred anyway, but to what degree?  Bush led the Republicans to ruin, but it was exacerbated by the grandstanding, media-centric undermining of “maverick” John McCain.  Furthermore, how many fewer people would have stayed home and at least helped blunt the hit to Republicans in Congress if the top of the Republican ticket hadn’t been so utterly revolting?  Yes, the Republicans would still have been in the minority, but politically irrelevant?  No.

Why bring this up at all?  Because we get to make the decision again in November of 2010 should the unfortunate happen and McCain makes it to the general election.  We already know that this year alone, he’s campaigned for RINOs in the primaries, and there was that whole mess with the Dorgan-McCain vitamin supplement fiasco.  It’s safe to say he hasn’t changed anything but his rhetoric, and we can expect the same sorts of behavior from him we saw under Bush once he’s safely back in the Senate.

What then, and why would the Democrat be the lesser evil in that race?

1. Remember Lindsey Graham?  Well, McCain mentored him in 2002 to the Senator he is today.  Once he’s back in the Senate, he can “mentor” all the new Tea Party candidates on “how things actually work” in Washington.  In other words, break out the maverick cookie cutter and see how many more Grahams he can create.  The Democrat can’t do that.
2. McCain is a militant RINO WITH MASSIVE SENIORITY.  If anyone can and will short-circuit Tea Party gains in the Republican party by running roughshod over them after the election cycle, he can and will.  His love of conservatism is strictly the stuff of campaign spin.
3. Yes, the Democrat will back Obama, but only McCain can hamstring resistance to the Obama agenda from the inside.  He can browbeat junior Republicans, organize moderates, and grant the cover of bipartisanship where a Democrat cannot.  That’s more damage than a junior Democrat can do as an honest opponent.
4. The Democrat can’t run around the country recruiting liberal Republicans.  They could try, but it would only be good for a laugh track.  McCain can and has, though fortunately he’s lacked much success.  So far, Fiorina’s and Kirk’s nominations have kept it from being a total recruiting wipeout for him, but it’s safe to assume he didn’t back them for their rock-ribbed conservatism.
5. Now let’s say Sarah Palin wins the Presidency in 2012.  Given McCain’s behavior towards Bush for defeating him in the 2000 presidential primary, how is he going to react to the 4-year long constant reminder of exactly who the drag was on the McCain-Palin ticket?  Or proof that he’s been politically outdone in every conceivable measure by a VP candidate he never intended get this far?  Presuming his ego and sense of entitlement don’t outright detonate, it will make what he did under Bush seem a blessing by comparison.

It won’t be an inspiring general election if McCain is involved.  More like a choice between taking a punch to the gut or a Louisville Slugger to the knees.  But think back to 1998 before you reflexively support The Danged Maverick.

P.S.:  I honestly hope Hayworth renders all of this hypothesizing moot.  There’s still time before the 24th to help him.

Addendum, 8/7/2010:  Added point #5, second list.