underdog position

[Sepmre]

Hi,
Could anyone please tell me what the underlined part means?

According to Advertising Age, the Avis “We Try Harder” campaign was one of the top 10 in advertising history. It was the ultimate simple idea that conveyed a great idea that was truthful and believable. The strategy—to state strongly a self-effacing underdog position—also tapped into people’s sympathy for underdogs.

 

[Tarheel]

Their slogan was:

We're number two. We try harder.

It exploits sympathy for the underdog. (Hertz was the big dog, or top dog.)

 

[GoesStation]

The strategy exploited the sympathy people have for those who come in second place. This strategy said emphatically but self-mockingly that Avis was aware it was not the leader.