AUBURN, Calif.  While most Congressional races are known for incumbency comfort, a nasty battle over the seat held since 1993 by John T. Doolittle  a Republican who decided not to seek re-election after coming under fire over his ties to a convicted lobbyist  has shaken up this reliably conservative spot on the California map.

The race, for one of only two open Congressional seats in the state, has intrigued Californians and raised hopes among Democrats nationwide that this might just be the year they flip a seat that for decades has been reliably Republican.

On the Republican side, the battle has pitted Tom McClintock, a well-known state legislator and frequent candidate, against Doug Ose, a former congressman. Their primary race has embroiled the state’s Republican Party over endorsement rules, and forced the residents of the state’s Fourth Congressional District  which runs from the eastern Sacramento suburbs to the Oregon border  to ponder why the two men wishing to represent them do not actually live among them.

Waiting in the general-election wings is Charlie Brown, a plain-spoken former Air Force helicopter pilot and Democrat whose support of gun rights and small-government-preaching attitude is probably nearer to Mr. Doolittle than to most members of his party. Mr. Brown came within 9,000 votes of unseating Mr. Doolittle in 2006.