Yes, they can. In fact, with the growing presence of startups on the web, PPC is one strategy that gives online branding and marketing the push that it needs in the case of startups.
While SEO has had a long-standing reputation for organic brand building (which is a great thing) over the Internet, in case of startups, organizations have a limited time to make it. Most startups that fail, fail within the first 3 years of operation. Not being able to gain traction among the target audience is one of the major contributors to such failure.
With limited time at hand, there is a lot that pay per click ads can do for you. They can:
Build your brand by increasing your online presence
Give you insights into your target audience’s search and clicking behaviors
Engage your audience in a more customized way (rather than SEO with alone)
Run the ads as per your budget and still offer quick results
Let you analyze weekly progress
Work extremely well for local audience