It is a very Republican district, but I question your implication that Holden has largely won b/c of GOP incompetence. After they screwed him with the redistricting -- and he still won -- I think the state party basically decided that its resources could be better used elsewhere. Honestly, I question whether ANY republican can beat Holden at this point absent a huge GOP year.
Tim definitely isn't my favorite Democrat, but there's no doubting that he's a heck of a politician. I can't imagine any other Democrat holding that seat, but I think it's safe as long as he wants to stay in Congress.
I was in Gekas's district prior to 2002 but was redistricted elsewhere, so I don't have any direct knowledge of Holden from a constituent or campaign viewpoint--but I have seen him make the political rounds in Dauphin County very efficiently.
I'll cede your superior knowledge that he'd be really hard to beat, but don't give the state GOP credit for deciding to use its assets elsewhere. It doesn't seem to have competently addressed any political situation for some years now.
Then again, I don't see any Republican candidates on the horizon who could challenge Holden. Piccola seems to desperately want to move up, but the state party wouldn't back him for gov or judge. I think he's like Casey in wanting to stay in the state, but maybe a GOP Schumer would make him an offer he can't refuse. (Or maybe the state party estimates him correctly, and he just gets good press from the Patriot-News; anyway, he's the only Republican in the district I've heard much of anything good about.)
So what is the R/D percentage in the district?
(Oh, and my family and friends--pre-Dean, I did nothing political beyond showing up on election day--considered Gekas a joke, somebody who played the piano in senior centers and lacked gravitas; did he run unopposed in previous years? I voted in that district in 1996, 1998, and 2000, but I don't remember.)