To an extent.
I'm a big advocate of reading about other campaigns to learn about how to run your own. In that vein, I recently read Game Change, which chronicled the 2008 presidential election. It's a great read if you're interested in how campaigns work, particularly at the presidential level. It is particularly helpful in understanding how candidate's messages are perceived by voters.
Back to the assertion that in every election, the incumbent defines the race. On page 64 of the book, the authors John Heilemann and Mark Halperin write:
[Obama strategist David] Axelrod had a complementary view, which he laid out for Obama. In every election, Axelrod argued, the incumbent defines the race, even if he isn't on the ballot. Which meant 2008 was going to be defined by Bush. And given the enmity that the president had inspired in the Democratic Party, Axelrod went on, the overwhelmingly liberal primary and caucus electorate would be hungry for a candidate representing the sharpest possible departure from 43: one who promised to be a unifier and not a polarizer; someone non dogmatic and uncontaminated by the special-interest cesspool that Washington had become; and, critically, someone seen as a staunch and principled opponent of the war raging in Iraq. Now, who had a better chance of being that someone - Hillary or Barack? The question answered itself.
We all remember the three-word mantra of the Obama campaign: Hope and Change. Hope [that the future would be better than the present, under Bush] and Change [from the policies of the Bush administration]. The campaign's message, boiled down to three words, clearly embraced the idea that the campaign was about Bush.
So, how does that translate to your campaign?
Remember that voters will view your candidacy through the lens of the incumbent, even if you're running for an open seat and the incumbent isn't on the ballot.
When determining what the message of your campaign will be, be sure to consider what the voters know about and think about the incumbent. Then you can determine whether to contrast yourself with the incumbent or embrace him in a "don't change horses in midstream" style of campaign.
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