There are some good tip threads hidden around the site.
Clinton wiped me out the first time I ran against him in Campaign mode (with Dubya). The second time, I wiped him out with about 370 EVs.
The strategy some others have described was a good starting point. For the first half of the game or so, I just built Level 3 HQs and did multiple fundraisings in the biggest competitive states, and banked PC when I couldn't afford to build. I used the PC to get endorsements. I think I got half of them, or half plus one. I didn't do any ads. I also moved the Political Operatives from my HQs into the southern states (MS, AL, GA, LA, TN, etc) to start gaining a little Awareness in places I didn't plan to advertise much.
After the VP selection, I built one one Level 3 HQ, and then started a media blitz. I think I was down about 7 points nationally at the halfway point. I went into OH, PA, FL, WI and MN with Webmasters and about 3 or 4 TV ads each. Clinton was harping almost exclusively on two issues - Deficit Reduction and Prescriptions for Seniors. Rather than try to catch up (his ratings were around +100 in many states) I changed the subject. I concentrated on about 4 issues: War on Terror, Homeland Security, Fighting Crime, and More Jobs. I also threw in a Social Security ad in FL, a Public Education in PA, a Farm Subdidies in IA, etc. IIRC, this was all in place by about Week 30. Cheney still hadn't moved from Wyoming, where he was beefing up Awareness in all the neighboring states. I was also careful to try to monitor Awareness in states where I had my operatives, and move them somewhere else when it got to 100%. The Mississippi/Ohio valley was starting to look pretty good by then. The Deep South and Rocky Mountain areas were still blue, however, despite the efforts of my Operatives.
By this time, Webmasters were getting prohibitively expensive in terms of PC, but my net revenue was around $800K per week, thanks to the HQs and the Webmasters. Then I concentrated the operatives in the south and created more of the same Red Meat type TV ads, including Strong Military, into NC. As before, when I couldn't afford more TV ads, I either built up PC, or did an occasional fundraiser. I also threw a few ads into MO and IA to lock those down. Around Week 35 or so, the lower South and IL (where I never set foot all game) were turning red, and my Awareness was getting close to 100% everywhere in the South, so I sent the pack of five operatives into the Mountain West and IN, and moved Cheney to CO. Bush went to shore up AZ, which had been red since early in the game (Level 3 HQ, plus all my TV ads elsewhere and endorsements helped) but was starting to suffer from Deficit Reduction and Presciptions for Seniors issues. I threw the last couple TV ads in there (again sticking to my short-list of issues). The last "Fighting Crime" and "Homeland Security" ads in AZ turned the remainder of the plains states except ID red and NJ + DE into gray. I was practically broke in Week 41, and could only afford one last radio ad (the only one I placed all game) into NM, which impressed the Idahoans and even got me NJ and DE. In the last weeks, I also bought a couple Fixers and Spin Doctors to nail down AZ and avert an October surprise in OH. With my last Stamina, I gave a Homeland Security or War on Terror speech in MI, but it was the first time I'd set foot in the state all game, and it couldn't overcome the 6 point deficit.
The result, as I said, was close to a landslide. Clinton won every state bordering the Pacific, including AK and HI, New England, MD, MI and NY. I got everything else. I spent a bit over half as much cash, but used about 2-3 times as much PC (76, IIRC). In the Exit Polls, Clinton had the top two issues (Prescription Drugs - 21% and Deficit Reduction - 11%, but I had four out of the next five, I think, all around 10%..
So the lessons seem to be:
1) Build L3 HQs early in large battleground states
2) Use the resulting Operatives intelligently, not leaving them in states where Awareness is pegged, but sending them to "base" states where you won't build HQs or advertise much, if at all
3) Generate PC and grab endorsements when you can't afford to build HQs and aren't in a position to fundraise
4) I like to do multiple consecutive fundraisers in a given state. Tap it dry, then don't waste the money and stamina to come back later.
5) At about midway point, start the Webmaster-led media blitz. It's very important to focus on a handful of topics with broad support, as this not only builds up your issue ratings, it makes those issues more important all over the country (which makes your boosted ratings more valuable).
6) Don't try to fight the opponent on his strong issues; instead, refocus the national debate on your strong ones in a broader message, with a few state-specific issue ads thrown in.
7) Around Week 30, start doing non-Webmastered ads in the south, and in battleground states that are still Blue or Grey. This will start to eat into your cash, but you are in the home stretch.
8) Keep generating PC to spawn Fixers and Spin Doctors to put out any fires in the final weeks.
9) Feel Slick Willy's pain...
Now we'll see if it works against LBJ; not being able to take Texas for granted will be annoying...
